The Doctor has always considered himself a healer, someone who fixes whatever’s wrong, making everything better. He doesn’t understand how he became this man. He never wanted to be a soldier, a warrior, fighting this soul-destroying war.
He doesn’t deserve the name Doctor, not anymore, but after so many centuries of existence, it’s stuck in his head, his indelible identity.
Now he’s in possession of the most powerful weapon ever devised, fully intends to end the war by destroying Daleks and Time Lords alike. He doesn’t want to survive the destruction, but if that’s his punishment, then so be it.